I'm just doing a little experimenting and would like to test out the comparators on an 18F4520.

I don't need an interrupt or a internal reference voltage, I just want a zero-crossing-detector on comparator 2 and be able to view the results on my o-scope.

I'm starting to wonder if the comparator 2 output is even available on a pic pin ? It's labeled C2OUT, and the datasheet shows RA5 as C2OUT, but I'm not seeing any action on that pin.

The circuit :



The input / output (this is what I'm reading on the PIC pin RA1 and output on RA5)



Thanks .. please convey if you have any idea why I'm not seeing a nice square wave on RA5 of the pic !